const fs = require('fs');
const path = require('path');
const parse = require('csv-parse').parse;
const habitablePlanets = [];
function isHabitablePlanet(planet) {
    return planet['koi_disposition'] === 'CONFIRMED'
    && planet['koi_insol'] > 0.36 && planet['koi_insol'] < 1.11
    && planet['koi_prad'] < 1.6;
    }
    function loadPlanetsData() {
        return new Promise((resolve, reject) => {
        fs.createReadStream(path.join(__dirname, '..',
        '..', 'data', 'kepler_data.csv'))
        .pipe(parse({
        comment: '#',
        columns: true,
        }))
        .on('data', (data) => {
        if (isHabitablePlanet(data)) {
        habitablePlanets.push(data);
        }
        })
        .on('error', (err) => {
        console.log(err);
        reject(err);
        })
    .on('end', () => {
    console.log(`找到${habitablePlanets.length}
    个可居住星球！`);
    resolve();
    });
    });
    }
    module.exports = {
    loadPlanetsData,
    planets: habitablePlanets,
    };